To fix movable vehicle parts, such as for example, doors and tailgates, to a body of a motor vehicle, it has been known for a long time to use hinges. Recently, it is also known to make the entire hinge or at least the hinge bushes out of plastic, whereby inter alia a lower weight of the component can be achieved.
Hinges which may be composed of plastic are known, for example, from German Patent Publication No. DE 101 18 301 A1 or German Patent Publication No. DE 10 2011 100 048 A1.
Plastic bushes, however, when used in vehicle construction, have a serious disadvantage. For instance, during the conventional painting of bodies and doors which are mounted via hinges with plastic bushes, cathodic dip coating is performed. During the cathodic dip coating, because of the inadequate electrical conductivity between the hinge halves and the resulting arcing, a high number of painting defects, known as “blisters” occur, leading to undesirable retouching work and corrosion problems.
The conductance of these plastic bushes may indeed be increased by using more electrically conductive materials, in particular, by adding carbon to the material of the hinge. This in turn, however, leads to excessive adhesion of the cathodic dip coating in the outer region of the hinge. The attached cathodic dip coating may then detach on movement of the hinge and, for example, cause contamination to the vehicle body. This process, therefore, also requires undesirable retouching work after the painting process.